Dual-Located WHIRLY1 Interacting with LHCA1 Alters Photochemical Activities of Photosystem I and Is Involved in Light Adaptation in Arabidopsis

• Published in: International journal of molecular sciences 2017-11, Vol.18 (11), p.2352
• Main Authors: Huang, Dongmei, Lin, Wenfang, Deng, Ban, Ren, Yujun, Miao, Ying
• Format: Article
• Language: English
• Subjects: Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Chlorophyll; Chlorophyll Binding Proteins - genetics; Chlorophyll Binding Proteins - metabolism; Chloroplasts - genetics; Chloroplasts - metabolism; Coding; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Electron transport; Electron transport chain; electron transport rate (ETR); Flowers & plants; Fluorescence; Gene expression; Genes; Jasmonic acid; Leaves; Light; Light adaptation; NADPH dehydrogenase; Nuclei; photochemical activities; Photochemistry; Photosynthesis; Photosynthesis - genetics; Photosynthesis - physiology; Photosystem I; Photosystem I Protein Complex - genetics; Photosystem I Protein Complex - metabolism; plastid gene; Plastids; Protein Binding; Quenching; Reactive oxygen species; Redox properties; Senescence; WHIRLY1
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms18112352

Plastid-nucleus-located WHIRLY1 protein plays a role in regulating leaf senescence and is believed to associate with the increase of reactive oxygen species delivered from redox state of the photosynthetic electron transport chain. In order to make sure whether WHIRLY1 plays a role in photosynthesis, in this study, the performances of photosynthesis were detected in knockout ( ) and plastid localized WHIRLY1 overexpression ( ) plants. Loss of WHIRLY1 leads to a higher photochemical quantum yield of photosystem I Y(I) and electron transport rate (ETR) and a lower non-photochemical quenching (NPQ) involved in the thermal dissipation of excitation energy of chlorophyll fluorescence than the wild type. Further analyses showed that WHIRLY1 interacts with Light-harvesting protein complex I (LHCA1) and affects the expression of genes encoding photosystem I (PSI) and light harvest complexes (LHCI). Moreover, loss of WHIRLY1 decreases chloroplast NAD(P)H dehydrogenase-like complex (NDH) activity and the accumulation of NDH supercomplex. Several genes encoding the PSI-NDH complexes are also up-regulated in and the double mutant ( ) but steady in plants. However, under high light conditions (800 μmol m s ), both and plants show lower ETR than wild-type which are contrary to that under normal light condition. Moreover, the expression of several PSI-NDH encoding genes and which is related to jasmonate (JA) response varied in under different light conditions. These results indicate that WHIRLY1 is involved in the alteration of ETR by affecting the activities of PSI and supercomplex formation of PSI with LHCI or NDH and may acting as a communicator between the plastids and the nucleus.